Classification of Thematic Maps

Types of Map Features Points Lines Areas

Qualitative, or Nominal

Descriptive Point Symbols on a Topographic Map

Descriptive Line Symbols on a Topographic Map

Contrasting Area Patterns on a Choropleth Map or a Topographic Map

Ranked, or Ordinal

Classified Graduated Symbols Map Classified Flow Map

Classified Choropleth Map

Classified Graduated Symbols Map

Dat

a Le

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f M

easu

rem

ent

Quantitative, or Interval/Ratio

Discrete Phenomena Proportional Graduated

Symbols Map Continuous Phenomena

Isolines Map

Proportional Flow Map

Absolute Counts Dot Map Cartogram Proportional Graduated

Symbols Ratios or Densities Classless Choropleth MapIsolines Map